Glycol ethers are a class of chemical compounds consisting of

alkyl In organic chemistry, an alkyl group is an alkane missing one hydrogen. The term ''alkyl'' is intentionally unspecific to include many possible substitutions. An acyclic alkyl has the general formula of . A cycloalkyl group is derived from a cy ...

ether In organic chemistry, ethers are a class of compounds that contain an ether group, a single oxygen atom bonded to two separate carbon atoms, each part of an organyl group (e.g., alkyl or aryl). They have the general formula , where R and R� ...

s that are based on

glycols A diol is a chemical compound containing two hydroxyl groups ( groups). An Aliphatic compound, aliphatic diol may also be called a glycol. This pairing of functional groups is pervasive, and many subcategories have been identified. They are used ...

such as

ethylene glycol Ethylene glycol ( IUPAC name: ethane-1,2-diol) is an organic compound (a vicinal diol) with the formula . It is mainly used for two purposes: as a raw material in the manufacture of polyester fibers and for antifreeze formulations. It is an odo ...

propylene glycol Propylene glycol ( IUPAC name: propane-1,2-diol) is a viscous, colorless liquid. It is almost odorless and has a faintly sweet taste. Its chemical formula is CH3CH(OH)CH2OH. As it contains two alcohol groups, it is classified as a diol. An al ...

. They are commonly used as solvents in

paint Paint is a material or mixture that, when applied to a solid material and allowed to dry, adds a film-like layer. As art, this is used to create an image or images known as a painting. Paint can be made in many colors and types. Most paints are ...

s and cleaners. They have good solvent properties while having higher boiling points than the lower-molecular-weight ethers and

alcohol Alcohol may refer to: Common uses * Alcohol (chemistry), a class of compounds * Ethanol, one of several alcohols, commonly known as alcohol in everyday life ** Alcohol (drug), intoxicant found in alcoholic beverages ** Alcoholic beverage, an alco ...

History

The name "Cellosolve" was registered in 1924 as a United States trademark by Carbide & Carbon Chemicals Corporation (a division of Union Carbide Corporation) for "Solvents for Gums, Resins, Cellulose Esters, and the Like". "Ethyl Cellosolve" or simply "Cellosolve" consists mainly of ethylene glycol monoethyl ether and was introduced as a lower-cost solvent alternative to ethyl lactate. "Butyl Cellosolve" ( ethylene glycol monobutyl ether) was introduced in 1928, and "Methyl Cellosolve" ( ethylene glycol monomethyl ether) in 1929.

Types

Glycol ethers are designated "E-series" or "P-series" for those made from

ethylene oxide Ethylene oxide is an organic compound with the chemical formula, formula . It is a cyclic ether and the simplest epoxide: a three-membered ring (chemistry), ring consisting of one oxygen atom and two carbon atoms. Ethylene oxide is a colorless ...

propylene oxide Propylene oxide is an epoxide with the molecular formula C3H6O. This colourless volatile liquid with an odour similar to ether, is produced on a large scale industrially. Its major application is its use for the production of polyether polyols f ...

, respectively. Typically, E-series glycol ethers are found in pharmaceuticals, sunscreens, cosmetics, inks, dyes and water-based paints, while P-series glycol ethers are used in degreasers, cleaners, aerosol paints and adhesives. Both E- and P-series glycol ethers can be used as intermediates that undergo further chemical reactions, producing glycol diethers and glycol ether acetates. P-series glycol ethers are marketed as having lower toxicity than the E-series.

Health impacts

Most glycol ethers are water-soluble, biodegradable and only a few are considered toxic. In the early 1990s, studies found higher than expected rates of miscarriages among women who worked in semiconductor plants, which was traced back to glycol ethers used in the photoresist substances that coat

semiconductors A semiconductor is a material with electrical conductivity between that of a conductor and an insulator. Its conductivity can be modified by adding impurities (" doping") to its crystal structure. When two regions with different doping levels ...

. One study suggests that occupational exposure to glycol ethers is related to low motile sperm count, a finding disputed by the chemical industry.

Subclasses

Solvents

* Ethylene glycol monomethyl ether (2-methoxyethanol, CH₃OCH₂CH₂OH) * Ethylene glycol monoethyl ether (2-ethoxyethanol, CH₃CH₂OCH₂CH₂OH) * Ethylene glycol monopropyl ether (2-propoxyethanol, CH₃CH₂CH₂OCH₂CH₂OH) * Ethylene glycol monoisopropyl ether (2-isopropoxyethanol, (CH₃)₂CHOCH₂CH₂OH) * Ethylene glycol monobutyl ether (2-butoxyethanol, CH₃CH₂CH₂CH₂OCH₂CH₂OH), a widely used solvent in paintings and surface coatings, cleaning products and inks * Ethylene glycol monophenyl ether (2-phenoxyethanol, C₆H₅OCH₂CH₂OH) * Ethylene glycol monobenzyl ether (2-benzyloxyethanol, C₆H₅CH₂OCH₂CH₂OH) * Propylene glycol methyl ether, (1-methoxy-2-propanol, CH₃OCH₂CH(OH)CH₃) * Diethylene glycol monomethyl ether (2-(2-methoxyethoxy)ethanol, methyl carbitol, CH₃OCH₂CH₂OCH₂CH₂OH) * Diethylene glycol monoethyl ether (2-(2-ethoxyethoxy)ethanol, carbitol cellosolve, CH₃CH₂OCH₂CH₂OCH₂CH₂OH) * Diethylene glycol mono-n-butyl ether (2-(2-butoxyethoxy)ethanol, butyl carbitol, CH₃CH₂CH₂CH₂OCH₂CH₂OCH₂CH₂OH) * Dipropyleneglycol methyl ether *

C12-15 pareth-12 C12-15 pareth-12 ( INCI name) is an emulsifier and surfactant commonly used in cosmetics formulations. It is a polyethylene glycol ether formed by combining synthetic C12–C15 fatty alcohols with 12 moles of ethylene oxide. According to t ...

a polyethylene glycol ether used as an emulsifier in cosmetics

Dialkyl ethers

* Ethylene glycol dimethyl ether (dimethoxyethane, monoglyme, CH₃OCH₂CH₂OCH₃), a higher boiling alternative to

diethyl ether Diethyl ether, or simply ether, is an organic compound with the chemical formula , sometimes abbreviated as . It is a colourless, highly Volatility (chemistry), volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It belongs ...

and THF, also used as a solvent for polysaccharides, a reagent in organometallic chemistry and in some electrolytes of

lithium batteries Lithium battery may refer to: * Lithium metal battery, a non-rechargeable battery with lithium as an anode ** Lithium–air battery ** Lithium–iron disulfide battery ** Lithium–sulfur battery ** Nickel–lithium battery ** Rechargeable l ...

* Diethylene glycol dimethyl ether (1-Methoxy-2-(2-methoxyethoxy)ethane, diglyme, CH₃OCH₂CH₂OCH₂CH₂OCH₃) * Triethylene glycol dimethyl ether (2,5,8,11-Tetraoxadodecane, triglyme, CH₃OCH₂CH₂OCH₂CH₂OCH₂CH₂OCH₃) *

Tetraethylene glycol dimethyl ether Tetraethylene glycol dimethyl ether (TEGDME or tetraglyme) is a polar aprotic solvent with excellent chemical and thermal stability. Its high boiling point and stability makes it an ideal candidate for separation processes and high temperature reac ...

(2,5,8,11,14-Pentaoxapentadecane, tetraglyme, CH₃OCH₂CH₂OCH₂CH₂OCH₂CH₂OCH₂CH₂OCH₃) * Ethylene glycol diethyl ether (diethoxyethane, CH₃CH₂OCH₂CH₂OCH₂CH₃) * Ethylene glycol dibutyl ether (dibutoxyethane, CH₃CH₂CH₂CH₂OCH₂CH₂OCH₂CH₂CH₂CH₃)

Esters

* Ethylene glycol methyl ether acetate (2-methoxyethyl acetate, CH₃OCH₂CH₂OCOCH₃) * Ethylene glycol monoethyl ether acetate (2-ethoxyethyl acetate, CH₃CH₂OCH₂CH₂OCOCH₃) * Ethylene glycol monobutyl ether acetate (2-butoxyethyl acetate, CH₃CH₂CH₂CH₂OCH₂CH₂OCOCH₃) * Propylene glycol methyl ether acetate (1-methoxy-2-propanol acetate)

References

{{reflist Commodity chemicals